If you have been reading about room acoustics, the multitude of facts may be confusing. Here are questions and answers to clear up the confusion:
1. Q: Is it true that in small spaces (bedrooms, living rooms, etc.) modes and standing waves are #1 concern?
A: Yes (when you’re talking bass response). Early reflections are right up there with #1 priority, but those are a lot easier to fix.
2. Q: In small rooms, can you actually have the low end under control sufficiently to record double bass or mix records with a subwoofer or is it practically impossible?
A: Not impossible, but sometimes difficult. Depends a lot on the shape of the room. If you’re in say a perfect square, it is going to be a lot harder to get the modes under control because a few certain frequencies are going to build up like crazy. Bass traps and more bass traps is about all I can suggest. The more space you are willing to give up for them, the better.
3. Q: In which situations are ceiling clouds used? Do they replace or complement the more common wall panels?
A: Clouds are used to kill the early reflections coming off the ceiling between you and your monitors. A lot of people use thin panels for this (1-2 inches). Mine is 46 feet. 8 inches thick spaced 4 inches from the ceiling. It doubles as a bass trap for floor to ceiling modes. Works pretty well, but my ceiling is strong enough to support it. Clouds are put up in addition to the wall panels. Results are less comb filtering (cleaner frequency response), better stereo imaging, and obviously less reverb time in the room as a whole. Just like what wall panels in early reflection zones do.
4. Q: Should I start room treatment with some measurements or just go ahead and buy general-purpose acoustic panels?
A: Websites usually have recommendations for your room size. I would NOT use acoustic foam exclusively. That stuff is not really worth much for catching bass. Ok for highs and some mids though. Your room will (most likely) sound dull and boxy if you just putting up a lot of thin panels. You need some density and thickness to catch lows. Either way you go (building your own or going pre fab), rockwool or Owens Corning 703/705 (or a similar knockoff of it) is best.
5. Q: Is carpet on the floor a good or bad idea?
A: Seems like the majority of people prefer floor to carpet when it comes to audio.